1. Added debug logs for sync process

2. Micro refactoring

src/django_clickhouse/clickhouse_models.py

@@ -236,7 +236,10 @@ class ClickHouseModel(with_metaclass(ClickHouseModelMeta, InfiModel)):
 
                 with statsd.timer(statsd_key.format('steps.get_operations')):
                     operations = storage.get_operations(import_key, cls.get_sync_batch_size())
-                    statsd.incr(statsd_key.format('operations'), len(operations))
+
+                statsd.incr(statsd_key.format('operations'), len(operations))
+                logger.debug('django-clickhouse: got %d operations from storage (key: %s)'
+                             % (len(operations), import_key))
 
                 if operations:
                     with statsd.timer(statsd_key.format('steps.get_sync_objects')):
@@ -245,13 +248,18 @@ class ClickHouseModel(with_metaclass(ClickHouseModelMeta, InfiModel)):
                     import_objects = []
 
                 statsd.incr(statsd_key.format('import_objects'), len(import_objects))
+                logger.debug('django-clickhouse: got %d objects to import from database (key: %s)'
+                             % (len(import_objects), import_key))
 
                 if import_objects:
                     with statsd.timer(statsd_key.format('steps.get_insert_batch')):
                         # NOTE I don't use generator pattern here, as it move all time into insert.
-                        # That makes hard to understand where real problem is in monitoring
+                        #  That makes hard to understand where real problem is in monitoring
                         batch = tuple(cls.get_insert_batch(import_objects))
 
+                    logger.debug('django-clickhouse: formed %d ClickHouse objects to insert (key: %s)'
+                                 % (len(batch), import_key))
+
                     with statsd.timer(statsd_key.format('steps.insert')):
                         cls.insert_batch(batch)
 
@@ -312,7 +320,10 @@ class ClickHouseMultiModel(ClickHouseModel):
 
                 with statsd.timer(statsd_key.format('steps.get_operations')):
                     operations = storage.get_operations(import_key, cls.get_sync_batch_size())
-                    statsd.incr(statsd_key.format('operations'), len(operations))
+
+                statsd.incr(statsd_key.format('operations'), len(operations))
+                logger.debug('django-clickhouse: got %d operations from storage (key: %s)'
+                             % (len(operations), import_key))
 
                 if operations:
                     with statsd.timer(statsd_key.format('steps.get_sync_objects')):
@@ -321,6 +332,8 @@ class ClickHouseMultiModel(ClickHouseModel):
                     import_objects = []
 
                 statsd.incr(statsd_key.format('import_objects'), len(import_objects))
+                logger.debug('django-clickhouse: got %d objects to import from database (key: %s)'
+                             % (len(import_objects), import_key))
 
                 if import_objects:
                     batches = {}
@@ -331,7 +344,10 @@ class ClickHouseMultiModel(ClickHouseModel):
                                 # NOTE I don't use generator pattern here, as it move all time into insert.
                                 # That makes hard to understand where real problem is in monitoring
                                 batch = tuple(model_cls.get_insert_batch(import_objects))
-                                return model_cls, batch
+
+                            logger.debug('django-clickhouse: formed %d ClickHouse objects to insert'
+                                         ' (model_cls: %s, key: %s)' % (len(batch), model_cls.__name__, import_key))
+                            return model_cls, batch
 
                         res = exec_multi_arg_func(_sub_model_func, cls.sub_models, threads_count=len(cls.sub_models))
                         batches = dict(res)

src/django_clickhouse/storages.py

@@ -251,7 +251,7 @@ class RedisStorage(with_metaclass(SingletonMeta, Storage)):
         self.post_batch_removed(import_key, batch_size)
         self.get_lock(import_key, **kwargs).release()
 
-        logger.info('django-clickhouse: synced %d items (key: %s)' % (batch_size, import_key))
+        logger.info('django-clickhouse: removed %d operations from storage (key: %s)' % (batch_size, import_key))
 
     def post_sync_failed(self, import_key, **kwargs):
         # unblock lock after sync completed

src/django_clickhouse/tasks.py

@@ -1,5 +1,6 @@
 import datetime
 import importlib
+from typing import Type, Union
 
 from celery import shared_task
 from django.conf import settings
@@ -11,7 +12,7 @@ from .utils import get_subclasses, lazy_class_import
 
 
 @shared_task(queue=config.CELERY_QUEUE)
-def sync_clickhouse_model(model_cls) -> None:
+def sync_clickhouse_model(model_cls: Union[Type[ClickHouseModel], str]) -> None:
     """
     Syncs one batch of given ClickHouseModel
     :param model_cls: ClickHouseModel subclass or python path to it
@@ -25,7 +26,7 @@ def sync_clickhouse_model(model_cls) -> None:
 
 
 @shared_task(queue=config.CELERY_QUEUE)
-def clickhouse_auto_sync():
+def clickhouse_auto_sync() -> None:
     """
     Plans syncing models
     :return: None